Bituminous compositions



United States Patent "ice 13 Claims. (Cl. 106-269) This invention relates to bituminous compositions of the type that are mixed with mineral aggregates in the construction of asphalt pavements. More particularly the invention relates to a novel group of bonding agents which are adapted to be incorporated in such bituminous compositions and when so incorporated not only improve the bonding effectiveness of the bituminous composition but also exhibit improved thermal stability as compared with the bonding agents previously used.

It is known in the art of manufacturing bituminous compositions that the coating and bonding qualities of such compositions when mixed with mineral aggregates in the construction of asphalt pavements can be improved by addition thereto of certain chemical agents. The use of these agents has made is possible to use wet aggregates in preparing paving mixtures, thus making it unnecessary to have dry aggregates available and eliminating delays in road construction. Also the incorporation of such bonding agents in bituminous paving compositions has made it possible to use hydrophilic aggregates which could not be otherwise used. Moreover the use of these chemical bonding agents has brought about an improvement in the structural stability of the finished bituminous pavement by decreasing the tendency of the aggregate and bitumen to separate when exposed to water. Thus these agents have been useful in improving the method of asphalt road construction and improving the quality and length of service of the finished pavement.

However, in general these previously proposed bonding agents have been subject to the deficiency that they do not remain stable at elevated temperatures. In many instances it is common practice to store bituminous compositions, after they have been prepared, in tanks at an elevated temperature of say 250400 F. and maintain them in a fluid state so that the composition can be readily removed without the re-heating that would be necessary if the composition were allowed to cool and solidify. The period of storage may be as long as 14 days. In other cases quantities of asphalt or light bitumen are heated as high as 400-500 F. at the time of shipment so that the temperature upon arrival at the point of destination will have dropped to about 300-350 R, which is the desirable temperature required for proper application in preparing the paving mixture.

In general the previously proposed bonding agents are incapable of withstanding such elevated temperatures; when subjected to such temperatures they rapidly lose their effectiveness and become of little value as bonding agents. Accordingly it is an object of the present invention to provide a novel group of compounds which are adapted to be incorporated in bituminous paving compositions to improve the coating properties of the composition for wet aggregates and which retain their bonding efiectiveness when subjected to the elevated temperatures encountered during the storage and handling of asphalt compositions.

In accordance with the present invention the foregoing objective is achieved by incorporating in bituminous compositions one or more compounds selected from the class of amides of N,N,N-tri(aminoalkyl) amines and their salts. It has been found that when small amounts of 2,996,539.? Patented Aug.- 15, 19 61 such compounds are incorporated in a bituminous com-' position, the coating and bonding properties of the composition for wet aggregates is substantially improved and this improvement is retained even when the bituminous composition is maintained at elevated temperatures for extended periods of time.

The amides and amide salts of the present inventio include the nine classes indicated below: 7 r

(1) Mono-amides having the general formula:

ROO-NHA H2NAN H2NA wherein RC0 is an acyl group derived from an organic acid having from 10-20 carbon atoms, and A is an aliphatic hydrocarbon group having from 2-6 carbon atoms. In this formula the three A groups may have different numbers of carbon atoms.

(2) Di-amides having the general formula:

BOO-NH-A RCO-NH-A-N HEN-A wherein RC0 is an acyl group derived from an organic acid having from 2-20 carbon atoms and A has the same definition as in Formula 1. In this formula the two RCO groups may be different and at least one RCO group should be derived from acid containing 10-20 carbon atoms.

(3) T ri-amides having the general formula:

RCO-NHA RCO-NHAN RCONHA wherein RC0 is an acyl group derived from an organic acid having from 2-20 carbon atoms; A is defined as in Formula 1; the three RCO groups may be different; andv atleast one RCO group is derived from an acid having 10-20 carbon atoms. 7 (4) A mono-amide-mono-salt having the general formula:

RCO-NH-A EDN-A-NHO-OOR HaN-A wherein RC0 is an acyl group derived from an acid having 10-20 carbon atoms; A is defined as in Formula 1; and the two RCO groups may be different.

(5) A di-amide-mono-salrt having the general formula:

RCO-NH-A R0 ONHAN.HOO o R HzNA wherein RC0 is an acyl group derived from an organic acid having 2-20 carbon atoms; A is defined as in Formula 1; the RC0 group of the salt-forming acid and at least one of the other R00 groups is derived from an acid having 10-20 carbon atoms; and the several R00 groups may be derived from diiferent acids.

(6) A tri-amide-mono-sa-lt having the general formula:

RCO--NHA R C ONH-AN.HOO O R RCONHA wherein RC0 and A have the same definitions as in" Formula 5. v

(7) A mono-amide disalt having the general formula:

RCO-NH-A RC OOH.HzNA-N.HO-O C R HaN-A wherein RC is an acyl group derived from an acid having2-20 carbon atoms; A has the same definitions as in Formula 1; the RC0 group of the amide-forming acid and at least one of the other RCO groups is derived from all-acid containing from -20 carbon atoms; and the severalRCO groups may be difierent. V V p (8) mono-amide-n'i-salt having-the general formula:

R'CO-NlI-A P V 1 RCO-OH.H2N-AN.H0-O on RCO- OILHzNT-A wherein RC0 and A have the same definitions as in Formula 7;

(9) A di-amide-di-sait having the general formula:

ROG-NH-A.

ECO-NH-A-NHO-O 0 R RCO-OH.NHi-A wherein RC0 and A have the same definitions" as in Formula 7; at least one of the amide-forming RCO groups is derived from an acidcontaining from 10-20 carbon atoms; and the several RCO groups may be different.

Typical compounds that come within the scope of the foregoing general formulae and are useful in accordance with the present invention are:

n aaC z zC z) 3 N,N,N-tris( 3 -oleoylaminopropyl) CnHsaC O'NHCHzCHzGH:

CmHnOONHCHiCEiGHiN onmlooNnomomcm named N (3' oleoylaminopropyl) N (3 palmitoylaminopropyl) -N- 3-linoleoylaminopropyl) amine;

named, N (3 acetamidopropyl) N,N bis(-3 palrni-v toylaminopropynamine;

named N,N bis(3 butyrylaminopropyl) N (3- linoleoylaminopropyl) amine; V

' (1H3 CrIHuCONHCHaCHCHzCHaCH1CHrI?'-CHCHzNHCOCrsHai named: N.- (6 linoleoylaminohexyl) N (3 oleoyl-i aminopropyl)-N-(2-palmitoylaminoisopropylamine. This 4 named oleic acid salt of N,N-bis(3-aminopropyl)-N-(3- palmitoylaminopropyl)amine;

named mixed linoleic, palmitic, and stearic acid 83.11; of NIN bis(3-aminopropyl) N (3-oleoylaminopropyl) amine;

named palmitic acid salt of N,N-bis(3-oleoylaminopropyl) -N- (3-aminopropyl) amine.

In, preparing the amides and amide salts of the present invention, organic'acids are reacted with tris(aminoalkyl)amines. Representative amines of this class that isoneofthe several compounds formed by aeylation with tris('2 aminoethyl)amine; (H NCH CH(CH N', named. N,N,'N-tris(2-aminoisopropyl) amine; (H NCH CHgCH CH CH CH N, named N,N,N-tri's(6-aminohexyDamine; H NCH 'CH CH -N(cH CH -Nl-lg) CH CH CH CH CH CH 'NH named N-(3-aminopropyl) -N-(2-aminoethyl) -N-( G-aminohexyl) amine.

As pointed. outabove, the acyl group of the salt-formingacid and at least one of the amide-forming acyl groups should. be derived from an organic acid having 10-20 carbon atoms and representative acids of this group that may be used are: oleic, linoleic, linolenic, lauric, palmitic, stearic, rosinacid; abietic acids, naphthenic acids, tall oil acids, or any acids derived from tall oils as well as mixtures of 'the foregoing acids. In cases-Where the present compounds contain more than one amide-forming acyl group, including at least one acyl group derived from an acid having 10-20 carbon atoms, the other acyl groups ofthet compound may be derived from acids containing fewer thanlOicarbon atoms. Representative acids of this group are: acetic, butyric, Z-ethylhexanoic, hexoic, caprylic, caproic, toluic, benzoic and Z-ethyI-butyric acids;

In preparing the amide-amines of the present invention a tri'(aminoalkyl)amine is mixed with a suitable organic acid, acyl'halide, or ester and heated at IUD-200 C. with agitation. The reaction with an organic acid may be consideredfas taking place in two stages; upon mixing, the amine salt of the organic acidis formed and during the heating process the salt is dehydrated with the elimina tionof lmol of water for each amide group. The meth ods. of making compounds of the type represented by Formulae 1-9 are indicated below.

To make the compounds of Formula 1 equimolar quantities of acid and amine are mixed to form an amine salt which is heated to convert the amine salt to an amide according to the following equations:

NHi-A The compounds of Formulae 2 and 3 may be prepared in thesame Wayas those of Formula 1 except that two andthreemols of acid'respectively are'used per molof amine;

ag-season iNHg-A In preparing the compounds of Formula 4 equimolar quantifies of acid and amine are mixed and heated to form an amide, and then a second mol of acid is mixed with the amide to form the salt.

The compounds -of Forin'ul-a 5 can be made by making a diamide as in Formula -2"a'nd then mixing a mol .oi acid therewith to form the salt.

The compounds of Formula 6 can be made by maliing a triamide as in Formula 3 and then mixing a mol of acid therewith to-form the salt, or they can also be made by the direct reaction of four mols of acid with one mol of the amine.

I The compounds of -Formulae 7- and 8 can be'ma'de by preparing a monoamide as in Formula 1 and the mixtwo or three mols of acid respectively therewith to form the salt.

. The compounds of Formula 9 can be made by preparing-a diamide as in Formula 2 and then mixing two mo of acid therewith to form a salt. v

RGONHA ;no0'- NH-A-N+Rco0H-- NHr-A i It will .be pevident that in the case of compounds such as those of Formulae 2 and 3, the compounds can be prepared by the addition of one mol of acid at a time with subsequent heating to form an amide group. Also wherethe several acyl groups of the compounds are derived from different acids, stepwise amidation is prefer- 'able' to-use, but simultaneous amidation can be carried out by using a mixture of the required acids. I

In order 'to point out more fully the nature of the present invention the following specific examples are given of illustrative methods of making certain of the present compounds:

Example I A mixture of three mols of linoleic acid and one mol of N (2 aminoethyl) .--N (2 aminoisopropyl) N (6-aminohexyl) amine was heated for six hours with agitation at C. Approximately three mols of water was distilled ofi-during this times. The material was cooled and mixed with one mol of oleic acid, giving the oleic acid salt of N-(2-linoleoylaminoethyl)-N-(2-linoleoylaminoisopropyl) N (6 linoleoylaminohexyl) amine. The product was thermally stable in asphalt and was an efiective agent for bonding asphalt to wet aggregate.

Example 11 A mixture o f one mol of palmitic acid and ten mols of N,N,N tris(2 aminoethyl) amine was heated and agitated at 150 C. for six hours. The mixture was then distilled at atmospheric pressure until half of its volume had been removed. I'Ihe-remaining volatile matter was removed by vacuum distillation, leaving as a residue mainly N,N bis(2 aminoethyl)-N-(2-palmitoylaminoethyl) amine. The product was thermally stable in asphalt and was an effective agent for bonding asphalt to wet aggregate.

" Example 111 One mol of material prepared as in Example II was mixed with twomols of tall oil. The resulting material,

A mixture of one "mol. of- 'N-(2-aminoethyD-N-(2-aminoisopropyl)-N-(6-aminohexyl)amine, one mol of oleic acid, one mol of linoleic acid, and one mol of palmitic acid was stirred and heated for six hours at 150 C.- The product-which was a mixture of triamides of these three acids, wasthermally stable in asphalt'and was an eifeetive agent for bonding asphalt to wet aggregate. 4

It has been found that when suitable quantities of 'the foregoing compounds, usually0.1 to 5% by weight, are incorporated in asphalt they confer on the asphalt the ability to efiectively coat wet aggregates and the improved coating and bonding properties of the asphalt are retained even when it is maintained at elevated temperatures for extended periods or time. In -factit has been found that the efiectiveness of the present compounds is sometimes enhanced by heating in asphalt, possibly due to the fact that compounds such as those represented by Formulae -1 'to' 5 and 7 are capable of reacting with further quantities of acid and may react with the naphthenic acids present in the asphalt.

It is of course to be understood that the foregoing examples are illustrative only and that numerous amidoamines and salts other than those specifically referred to fall within the scope of the general formulae given above "and can be incorporated in asphalt to achieve the advanrtagesoutlined at the beginning of the present specification.

This application is a division of our parent application, Serial No. 494,569, filed March 15, 1955, now Patent No.2,874,174. p I I We claim:

1. A bituminous composition essentially composed of a bituminous material and from 0.1 to 5% by weight of a'thermally stable bond-improving agent selected from the group consisting of amides of tris(am.inoalkyl) amines and salts of such amides, the amide-forming acids being organic carboxylic acids having from 2 to 20 carbon '7 atoms; an th s l fm-mug aside when pr sent, and a least one o t e m d e rm n ab ds behl g or an c carbb yli c d having f o t .2 a bon a ass- 2- A itumin u mp tion e s ntially bemu ed o a bitum n s m al a .f m -1 t9 5% by weigh of a thermally stable bond-improving agent having the gem eral formula:

wherein RC0 is an acyl group of an organiccerboxylic acid havin g 2-20 carbon atoms, at least one of said RCO groups is derived from an acid having 1-0-20 carbon 1 atoms, and the several RCO groups can be difierent; and A is an aliphatic hydrocarbon radical containing 2-6 carbon atoms, and the several A radicals can be different.

3. A bituminous composition essentially composed of a bituminous material and from 0.1 to 5% by weight of a thermally stable bond-improving agent having the ;gen-

eral formula: r

B9 ==NJE=A no or-nn-ni-n NEr-A wherein RC0 is an acyl group of an organic carboxylic acid having 2-20 carbon atoms, at least one of said RCO groups contains 10-20 carbon atoms, and the two RGO groups can be different; and A is an aliphatic hydrocarbbn r di al c n in ng carbon atoms, and the se e A radicals can be difierent.

4- A bit m us ompos ti n es ent ally compo d of a b t minous material ndirbm 0 119 5% by we h of her l y t e nddmprbr n a n basins the gen eral formula: l

wherein RC0 is an acyl group or an organic carboxylic acid having 10-20 carbon atoms; and A is an aliphatic hydrocarbon radical containing 2-6 carbon atoms, and the several A radicals can be difierent.

5. A bituminous composition essentially composed of 'a bituminous material and from 0.1 to 5% by weight of a thermally stable bond-improving agent having the generalformula:

brherein :RC9 is an a yl g oup of an or an \FVAIJIQXYHG ghaving .2- carbon atoms, the ;RC0 group of the salt-tam ng acid :and at least one ther RG storm s baiting from IO-2,0 carbon atomszandr he e ralil groups can be difierent; and A is an aliphatic hydrocarbon radical containing 2-6 carbon atoms, and the several A radicals can be different. s

7. A bituminous composition essentially composed .of a bituminous material and from 0,1 to 5% by weight of a the m ly s a e bo p o n agent h ing the eral formula: c

wherein RC0 is an acyl group of an organic carboxylic acid having 2-20 carbon atoms, the RC0 group of at least one of the salt-forming acids and at least one of the amide-forming RCO groups having from 10-20 carbon atoms, and the several RCO groups can be diiferent; and A is an aliphatic hydrocarbon radical containing 2-6 carbon atoms, and the several A radicals can be different.

8. A bituminous composition essentially composed of a bituminous material and from 0.1 to 5% by weight of a thermally stable bond-improving agent having the genr l formula wherein RC0 is an acyl group of an organic carboxylic acid having 10-20 carbon atoms, and the two RCO r ups can b d te e an A s a ahphat h dro rbon radical containing 2:6 carbon atoms, and the several A radicals can be different.

9. A bituminous composition essentially composed of a bituminous material and from 0.1 to 5% by weight Of a thermally stable bond-improving agent having the general formula:

herein RC0 is an acyl g o p o a o anic earbnxy i acid ha i 2 car on at m t e RC0 gr up o at le s on o h salt-forming a id a he am de-t mbs RCO group having from 10-20 carbon ato rrugpnd several RCO groups can be different; and A is an aliphatic hydrocarbon radical containing 2-6 .carbon atoms, and the several A radicals can'be difierent.

10. A bituminous composition essentially composed of a bituminous material and from 0.1 to 5% by weight of a thermally stable bond-improving agent having the general formula:

wherein RC0 is an acyl group of an organic carboxylic acid having 2.-2 0 carbon atoms, the amide-forming RCO g o p and a leas one other RC oup having f 1 :20 c r on a oms, and the se er ,RCO e b p 9 be different; and A s l nhatic hydr carbon frad qal containing 2-6 carbon atoms, and the several A radicals can be diiferent.

11. A bituminous composition essentially composedrgf a bituminous material and from 0.1 to 5% by weight of a thermally stable bond-improving agent which "is N-(2- linoleoylaminoethyl) -N-(2 linoleoylaminoisopropyl)-N- (6-linoleoylaminohexyl) amine.

12. A bituminous composition essentially composed of a b umin us m ter a a d t am 9-11 t .1 by w i h of a her al y t bl bn rimp b ins a n which i N- bi t :ami oethybi ne m tbyham nbb hr ami e.-

1'3- A bi umi us bmpbsi on s en y bi m ed bi b b tumino s m er and :f 'Q 9-.-. to 5 y w sh b a thermal y stable bendzimnm ins agent wh ch is a sh- 9 tall oil acid salt of N,N-bis(2-aminoethy1)-N-(2-pa1mi- 2,514,954 toylaminoethyl) amine. 2,844,599

References Cited in the file of this patent UNITED STATES PATENTS 5 130 4 4 2,508,924 Mertens May 23, 1950 971,023

10 Johnson et a1. July 11, 1950 Rendall et a1. July 22, 1958 FOREIGN PATENTS Australia Nov. 28, 1946 France Jan. 11, 1951 

1. A BITUMINOUS COMPOSITION ESSENTIALLY COMPOSED OF A BITUMINOUS MATERIAL AND FROM 0.1 TO 5% BY WEIGHT OF A THERMALLY STABLE BOND-IMPROVING AGENT SELECTED FROM THE GROUP CONSISTING OF AMIDES OF TRIS(AMINOALKYL)AMINES AND SALTS OF SUCH AMIDES, THE AMIDE-FORMING ACIDS BEING ORGANIC CARBOXYLIC ACIDS HAVING FROM 2 TO 20 CARBON ATOMS, AND THE SALT-FORMING ACIDS, WHEN PRESENT, AND AT LEAST ONE OF THE AMIDE-FORMING ACIDS BEING ORGANIC CARBOXYLIC ACIDS HAVING FROM 10 TO 20 CARBON ATOMS. 